Isomerization of proline-93 during the unfolding and refolding of ribonuclease A.
Isomerization of proline-93 during the unfolding and refolding of ribonuclease A.
复制标题
核糖核酸酶 A 解折叠和重折叠过程中脯氨酸 93 的异构化。
DOI：
10.1021/bi00272a006
复制
发表时间：
1983
期刊：
影响因子：
2.9
通讯作者：
Brandts,JF
中科院分区：
文献类型：
--
作者：
Lin,LN;Brandts,JF
摘要：利用异构体特异性蛋白水解的方法，直接监测了脯氨酸-93在RNase a展开和再折叠过程中的异构化过程，发现脯氨酸-93在天然蛋白中为100%顺式，在可逆展开蛋白中为70%顺式。在展开反应中，从100%顺式到70%顺式的变化是一个一阶过程，在8.5 M尿素中弛豫时间为140 s，在10 C中，从70%顺式到100%顺式的变化也是一个一阶过程，在0.3 M尿素中弛豫时间为90 s，在1.0 M尿素中弛豫时间为130 s，在2.0 M尿素中弛豫时间为310 s。平行实验测量了酶活性的恢复在折叠过程中
Lung-Nan Lin and John F. Brandts* abstract: Using the method of isomer-specific proteolysis, the isomerization of proline-93 has been monitored directly during the time course of the unfolding and refolding reactions of RNase A. It has been found that proline-93 is 100% cis in the native protein and70% cis in the reversibly unfolded protein. During the unfolding reaction, the change from 100% to 70% cis occurs as a first-order process with a relaxation time of 140 s in 8.5 M urea, 10 C. For refolding, thechange from 70% to 100% cis also occurs as a first-order process, with a relaxation time (10 C) of 90 s in 0.3 M urea, 130 s in 1.0 M urea, and 310 s in 2.0 M urea. Parallel experiments which measured the recovery of enzyme activity during refolding were